1. Field of the Invention
The present invention relates to a push type switch, and more particularly to a push type switch which is capable of creating an upscale impression when operating (pushing) the push type switch.
2. Description of the Related Art
Conventionally, a key switch is known which is comprised of a membrane substrate, a pair of fixed contact points, a click rubber, a frame, and a key top (see e.g. Japanese Laid-Open Patent Publication (Kokai) No. 2004-71306 (Paragraph numbers [0011] to [0014], FIG. 1))
The membrane substrate is disposed on a chassis e.g. of electronic equipment.
The pair of fixed contact points are provided on the membrane substrate.
The click rubber has a generally domed shape, and covers the pair of fixed contact points. The click rubber has a conductive rubber provided on an inner surface thereof. The conductive rubber is opposed to the pair of fixed contact points in a manner spaced therefrom.
The frame is opposed to the membrane substrate and the click rubber in a manner slightly spaced therefrom. The frame includes a slide guide that has a hollow cylindrical shape.
The key top has a sliding portion. The sliding portion is in the form of an octagonal column and inserted into the slide guide, such that it slides in the direction of the thickness of the chassis.
The slide guide and the sliding portion are coated with a grease for smooth sliding and reduction of generation of noise.
When the key top is pushed with a finger, the sliding portion is caused to slide to press the click rubber. When the click rubber is pressed to a certain extent, it is inverted in shape, i.e. changed from a convex state into a concave state, whereby the conductive rubber is brought into contact with the pair of fixed contact points. As a result, the pair of fixed contact points are closed. Further, when the click rubber is inverted in shape, a click feeling is created.
When the finger is released from the key top, the key top returns to its original position by the resilience thereof, and the conductive rubber moves away from the pair of fixed contact points.
An upscale impression is demanded of a push type switch disposed on an instrumental panel for an automotive vehicle.
To impart the upscale impression to the above key switch, it is envisaged to use an expensive material for the key top, or decorates the key top with a special color or pattern.
However, there was a limit to creating the upscale impression, unless an operation feeling in operating the key switch is enhanced.